In this article I argue that mercy does not prevent the imposition of harsh punishment from being morally permissible. This article has two parts. In the first part, I argue that mercy is an imperfect duty, because only such a duty-type explains the attributes that are commonly ascribed to mercy. In the second part, I argue that mercy does not present a sufficient moral reason against the regular imposition of harsh punishment because it neither undermines nor systematically overrides or weakens the retributive duties. This is in part because the imperfect duty to be merciful can be satisfied by actions taken in nonpunitive contexts alone. This is also in part because mercy is not particularly appropriate given the lack of positive desert of and good moral character in most of the culpable wrongdoers who deserve harsh punishment